Blockchain Quantum

Google Quantum Breakthrough Could Improve Proof-of-Stake

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The application of Google’s quantum computing technology could purportedly help improve the technology which underpins proof-of-stake (PoS) cryptocurrencies.

Quantum computing would create truly random numbers

PoS is a type of consensus algorithm where block creators are randomly chosen with probability proportional to their stake, while the algorithm of proof-of-work-based digital currencies uses mining.

However, the PoS variant has raised doubts regarding the integrity of random selections.

Scott Aaronson, a quantum theoretician at the University of Texas at Austin, told Fortune on Oct. 23 that quantum computing could assuage PoS-skeptics doubts, as a quantum supremacy experiment could generate certifiably random numbers. He previously wrote on his personal blog:

“A sampling-based quantum supremacy experiment could almost immediately be repurposed to generate bits that can be proven to be random to a skeptical third party (under computational assumptions). This, in turn, has possible applications to proof-of-stake cryptocurrencies and other cryptographic protocols. I’m hopeful that more such applications will be discovered in the near future.”

Google’s project challenges the Church-Turing thesis

On Oct. 23, Google published the results of its quantum supremacy experiment, which Aaronson peer-reviewed. In the experiment, “Sycamore” — a 54-qubit processor with quantum logic gates — took 200 seconds to sample one instance of a quantum circuit a million times. In contrast, IBM’s supercomputer Summit, which is purportedly the most powerful computer to date, would run such a calculation for 10,000 years.

Google states that its experiment is the first experimental challenge against the extended Church-Turing thesis — also known as computability thesis — which claims that traditional computers can effectively carry out any “reasonable” model of computation. In a dedicated blog post, Google explained:

“We first ran random simplified circuits from 12 up to 53 qubits, keeping the circuit depth constant. We checked the performance of the quantum computer using classical simulations and compared with a theoretical model. Once we verified that the system was working, we ran random hard circuits with 53 qubits and increasing depth, until reaching the point where classical simulation became infeasible. […] With the first quantum computation that cannot reasonably be emulated on a classical computer, we have opened up a new realm of computing to be explored.”

Is Bitcoin affected?

Previously, ex-Bitcoin Core developer Peter Todd poured cold water on fears that recent advances in quantum computing could endanger the security of Bitcoin (BTC) — which is a proof-of-work-based cryptocurrency. Todd concluded that financial impediments alone would keep Bitcoin free from potential trouble.